Conventional incandescent light bulbs have been in use since General Electric refined the filaments in 1913. These light bulbs grew to be in common use around the world until the introduction of compact fluorescent (CF) bulbs which produced the same quantities of light output while shedding substantially less heat as a product of light production. Light Emitting Diodes (LED) are now being used for light bulbs. LED light bulbs are more efficient than fluorescent tube lights and compact fluorescent light bulbs.
Compact fluorescent light bulbs have now replaced incandescent light bulbs to the extent that some states have banned the production of incandescent light bulbs. CF bulbs have dropped in price to almost the same level as incandescent light bulbs. LED light bulbs, while more efficient than CF bulbs are considerably more expensive.